does anyone know where to get sd card topo maps for garmin gps that show boundaries for national forest lands for the eastern united states?thanks

http://www.huntinggpsmaps.com/

That's the website to buy the chips, but they aren't offered for Texas on east, except for several of the upper Great Lakes states. You would have to go on the website and either call or email them to get an idea of how long it will be before the rest of the US is done. I have Wyoming and it's great!

does the garmin 24k topos differentiate between national forest land and other lands?

http://forums.gpsfiledepot.com/

Check this link out they may have what you need and they're free.